Bidirectional physiological information display

ABSTRACT

A patient monitor for displaying a physiological signal can include a visual element having a middle portion indicative of a transition in the physiological signal between physiological states. The visual element can also include first and second extremity portions, the first extremity portion extending from the middle portion in a first direction and the second extremity portion extending from the middle portion in a second direction. The visual element can also include an actionable value indicator to specify a value about the middle portion and the first and second extremity portions. The patient monitor can also include a processor configured to cause the value indicator to actuate in both the first and second directions according to changes in the physiological signal.

RELATED APPLICATIONS

This application claims priority from U.S. Provisional PatentApplication No. 61/252,083 filed Oct. 15, 2009, and entitled “DisplayingPhysiological Information,” and from U.S. Provisional Patent ApplicationNo. 61/331,087, filed May 4, 2010, entitled “Acoustic RespirationDisplay,” the disclosures of both of which are hereby incorporated byreference in their entirety.

This application also relates to the following U.S. patent applications,the disclosures of which are incorporated in their entirety by referenceherein:

Filing App. No. Date Title 60/893,853 Mar. 08, 2007 MULTI-PARAMETERPHYSIOLOGICAL MONITOR 60/893,850 Mar. 08, 2007 BACKWARD COMPATIBLEPHYSIOLOGICAL SENSOR WITH INFORMATION ELEMENT 60/893,858 Mar. 08, 2007MULTI-PARAMETER SENSOR FOR PHYSIOLOGICAL MONITORING 60/893,856 Mar. 08,2007 PHYSIOLOGICAL MONITOR WITH FAST GAIN ADJUST DATA ACQUISITION12/044,883 Mar. 08, 2008 SYSTEMS AND METHODS FOR DETERMINING APHYSIOLOGICAL CONDITION USING AN ACOUSTIC MONITOR 61/141,584 Dec. 30,2008 ACOUSTIC SENSOR ASSEMBLY 61/252,076 Oct. 15, 2009 ACOUSTIC SENSORASSEMBLY 12/643,939 Dec. 21, 2009 ACOUSTIC SENSOR ASSEMBLY 61/313,645Mar. 12, 2010 ACOUSTIC RESPIRATORY MONITORING SENSOR HAVING MULTIPLESENSING ELEMENTS 12/904,931 Oct. 14, 2010 ACOUSTIC RESPIRATORYMONITORING SENSOR HAVING MULTIPLE SENSING ELEMENTS 12/904,890 Oct. 14,2010 ACOUSTIC RESPIRATORY MONITORING SENSOR HAVING MULTIPLE SENSINGELEMENTS 12/904,938 Oct. 14, 2010 ACOUSTIC RESPIRATORY MONITORING SENSORHAVING MULTIPLE SENSING ELEMENTS 12/904,907 Oct. 14, 2010 ACOUSTICPATIENT SENSOR 61/252,099 Oct. 14, 2009 ACOUSTIC RESPIRATORY MONITORINGSYSTEMS AND METHODS 12/904,789 Oct. 14, 2010 ACOUSTIC RESPIRATORYMONITORING SYSTEMS AND METHODS 61/252,062 Oct. 15, 2009 PULSE OXIMETRYSYSTEM WITH LOW NOISE CABLE HUB 61/265,730 Dec. 01, 2009 PULSE OXIMETRYSYSTEM WITH ACOUSTIC SENSOR 12/904,775 Oct. 14, 2010 PULSE OXIMETRYSYSTEM WITH LOW NOISE CABLE HUB 12/905,036 Oct. 14, 2010 PHYSIOLOGICALACOUSTIC MONITORING SYSTEM 61/391,098 Oct. 08, 2010 ACOUSTIC MONITOR

Many of the embodiments described herein are compatible with embodimentsdescribed in the above related applications. Moreover, some or all ofthe features described herein can be used or otherwise combined withmany of the features described in the applications listed above.

BACKGROUND

Monitoring of respiratory activity in a patient is desirable in clinicalsituations since death or brain damage can occur within minutes ofrespiratory failure. As respiratory failure can be difficult to predict,continuous monitoring of respiratory activity is particularly beneficialin high-risk situations. Appropriate monitoring equipment saves lives.Moreover, respiratory monitoring equipment can also be useful fornon-critical care, including exercise testing and different types ofcardiac investigations.

A patient's respiratory activity can be monitored by an acousticrespiratory monitor. An acoustic respiratory monitor can include one ormore acoustic sensors that can be positioned on a patient's body toobtain acoustic respiratory information from a patient for analysis. Insome cases, the acoustic sensors may be positioned to detect trachealsounds, which can be heard at the suprasternal notch or at the lateralneck near the pharynx or at another location on the patient.

SUMMARY

In certain embodiments, a patient monitor for displaying a physiologicalsignal includes a visual element having a middle portion indicative of atransition in the physiological signal between physiological states. Thevisual element can also include first and second extremity portions, thefirst extremity portion extending from the middle portion in a firstdirection and the second extremity portion extending from the middleportion in a second direction. The visual element can also include anactionable value indicator to specify a value about the middle portionand the first and second extremity portions. The patient monitor canalso include a processor configured to cause the value indicator toactuate in both the first and second directions according to changes inthe physiological signal.

In certain embodiments, a method of displaying physiologicalinformation, implemented by a processor, includes providing a value of aphysiological parameter to a display of a patient monitor, where thephysiological parameter value reflects physiological informationobtained from a physiological sensor coupled to a patient. The methodcan further include calculating a freshness of the physiologicalparameter value and adjusting an output associated with the parametervalue based at least in part on the calculated freshness.

In certain embodiments, a method of displaying physiologicalinformation, implemented by a processor, includes outputting a value ofa physiological parameter to a display of a patient monitor, where thephysiological parameter value reflects physiological informationobtained from a physiological sensor coupled to a patient. The methodcan further include outputting a signal quality indicator reflecting aquality of the physiological information obtained from the physiologicalsensor, determining whether the value of the physiological parameter isvalid, and adjusting the signal quality indicator responsive to saiddetermination.

In certain embodiments, a method of displaying physiologicalinformation, implemented by a processor, can include providing a valueof a physiological parameter to a display of a patient monitor, wherethe physiological parameter value reflects physiological informationobtained from a physiological sensor coupled to a patient. The methodcan further include determining whether the value of the physiologicalparameter is valid, freezing an output associated with the physiologicalparameter value, calculating a freshness of the physiological parametervalue, in response to said freezing, and adjusting the output associatedwith the parameter value based at least in part on the calculatedfreshness.

Further, in some embodiments, a method is provided for displayingphysiological information on a physiological monitor that can be coupledto a patient sensor that can detect a physiological signal. The method,implemented by a processor, can include outputting a value indicator toa display of the patient monitor, expanding the value indicator in twodirections simultaneously in response to increasing values in aparameter measured from the physiological signal, and contracting thevalue indicator opposite the two directions simultaneously in responseto falling values of the measured parameter.

In certain embodiments, a method of displaying physiological informationon a physiological monitor, implemented by a processor, can includereceiving a physiological signal from a sensor coupled to a patient,where the physiological signal reflects a physiological parameter of thepatient. The method can further include activating a visual indicator ofa visual element to cause the visual indicator to illuminate from acentral region outwards toward both a first end region and a second endregion of the visual element and then inwards from the first and secondend regions toward the central region, responsive to changes in thephysiological parameter.

A physiological monitor can include, in certain embodiments, a processorthat can receive physiological information from one or more sensorscoupled with a patient and a display having a visual element forrepresenting values of a physiological parameter responsive to thephysiological information. The visual element can include a middleportion representing an initial position, first and second extremityportions, the first extremity portion extending from the middle portionin a first direction, and the second extremity portion extending fromthe middle portion in a second direction, and a value indicator that canilluminate starting from the initial position and expanding both to thefirst and second extremity portions, followed by contracting at leastpartway toward the middle portion, responsive to changes in thephysiological parameter.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the inventions have been described herein. It isto be understood that not necessarily all such advantages can beachieved in accordance with any particular embodiment of the inventionsdisclosed herein. Thus, the inventions disclosed herein can be embodiedor carried out in a manner that achieves or optimizes one advantage orgroup of advantages as taught herein without necessarily achieving otheradvantages as can be taught or suggested herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers can be re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the inventions described herein and not tolimit the scope thereof.

FIG. 1 is a depiction of an embodiment of a patient monitoring systemfor acquiring, processing, and displaying physiological information(e.g., respiratory-related information);

FIG. 2 is a schematic representation of an embodiment of a visualelement for use with the system of FIG. 1 to display a physiologicalsignal (e.g., a respiratory signal);

FIG. 3 is a schematic representation of an embodiment of a visualelement for use with the system of FIG. 1 to display a physiologicalsignal (e.g., a respiratory signal);

FIG. 4A is an embodiment of a series of depictions of the visual elementof FIG. 2 shown at different times as a physiological signal (e.g., arespiratory signal) fluctuates;

FIG. 4B is an embodiment of a flowchart that further describes theillustrations in FIG. 4A;

FIG. 5A is an embodiment of a series of depictions of the visual elementof FIG. 2 shown at different times as a physiological signal (e.g., arespiratory signal) fluctuates;

FIG. 5B is an embodiment of a flowchart that further describes theillustrations in FIG. 5A;

FIG. 6 is an embodiment of a schematic representation of a visualelement capable of simultaneously displaying a plurality of valuesassociated with a physiological signal (e.g., a respiratory signal) at aplurality of times;

FIG. 7A is an embodiment of a schematic representation of a visualelement, which includes peak indicators, for displaying a physiologicalsignal (e.g., a respiratory signal);

FIG. 7B is an embodiment of a flowchart that further describes theillustrations in FIG. 7A;

FIG. 8A is an embodiment of a schematic representation of a visualelement, which includes goal indicators, for displaying a physiologicalsignal (e.g., a respiratory signal)

FIG. 8B is an embodiment of a flowchart that further describes theillustrations in FIG. 8A; and

FIG. 9 is an embodiment of a schematic representation of a visualelement, which includes a plurality of types of indicators, fordisplaying a physiological signal (e.g., a respiratory signal).

FIG. 10 is an embodiment of a top perspective view illustrating anembodiment of a sensor assembly and cable.

FIG. 11 illustrates an embodiment of a respiratory analysis system.

FIG. 12 illustrates an embodiment of a physiological monitor having arespiration display.

DETAILED DESCRIPTION

Systems and methods of visually communicating information aboutphysiological signals (e.g., respiratory signals) to an observer aredescribed herein. In one embodiment, a physiological monitoring systemincludes one or more sensors to detect a physiological signal from apatient. For example, the physiological signal can be an acousticrepresentation of a respiratory signal detected by an acoustic sensor inthe vicinity of a patient. The physiological monitoring system can alsoinclude a display for communicating information about the physiologicalsignal to an observer, as well as a processor for processing thephysiological signal and controlling the display.

In some embodiments, the display includes a visual element with a valueindicator for visually communicating a value associated with aphysiological signal to an observer. The value indicator can have aninitial position and can expand or contract in a first portion of thevisual element during a first physiological state. The firstphysiological state can, for example, correspond to patient inspiration(or inhalation). The value indicator can expand or contract in a secondportion of the visual element during a second physiological state, whichcan correspond, for example, to patient expiration (or exhalation). Inother embodiments, the value indicator expands from a reference positionin at least two directions simultaneously, the reference position beingrepresentative of a transition between first and second physiologicalstates, such as patient inspiration and expiration.

Multidirectional Display

FIG. 1 illustrates a respiratory monitoring system 105 for monitoringthe respiratory activity of a patient 100. The respiratory monitoringsystem 105 includes a respiratory monitor 110 communicatively coupled toa sensor 120. The sensor 120 is positioned on the patient's body todetect respiratory sounds. In one embodiment, the sensor 120 includes apiezoelectric crystal transducer to transform sound vibrations in thepatient's body into electrical signals. Other types of sensors can alsobe used. The resulting electrical respiratory signal can be transferredto the respiratory monitor 110 via electrical leads 130, by wirelesstransmission, or any other appropriate method. Various sensors andmonitors adaptable to be used with any of the embodiments describedherein, have been described in the following applications and issuedpatents: U.S. Provisional No. 60/893,853, filed Mar. 8, 2007; U.S.Provisional No. 60/893,850, filed Mar. 8, 2007; U.S. Provisional No.60/893,858, filed Mar. 8, 2007; U.S. Provisional No. 60/893,856, filedMar. 8, 2007; U.S. application Ser. No. 11/547,570, filed Oct. 6, 2006;U.S. application Ser. No. 12/643,939, filed Dec. 21, 2009, and U.S. Pat.No. 6,661,161 (see also FIG. 10). Each of these references is herebyincorporated by reference in its entirety.

The respiratory monitor 110 can include circuitry to convert therespiratory signal into a digital format, as well as a processor (notshown) to analyze the respiratory signal. For example, the respiratorysignal can be processed or analyzed with a Fourier transform or othermathematical transform to determine or analyze the frequency content ofthe signal. The signal can also be time-averaged, filtered, amplified,or otherwise conditioned or analyzed using the processor. For example,the processor can be configured to determine a patient's inspiratorytime, expiratory time, inspiratory to expiratory ratio, inspiratoryflow, expiratory flow, tidal volume, minute volume, apnea duration,breath sounds—including rales, rhonchi, or stridor, changes in breathsounds, etc. Regardless of whether the acquired signal is in analog ordigital form, has been conditioned, transformed, or otherwise analyzedor altered, it can generally be referred to as a respiratory signal oracoustic signal throughout this disclosure.

Once the respiratory signal has been acquired by the sensor 120 andtransferred to the respiratory monitor 110, the signal, or aspects ofit, can be communicated to an observer by a visual element 150 of therespiratory monitor display 140. FIGS. 2-9 illustrate variousembodiments of the visual element 150. While certain embodiments can bedescribed primarily in the context of displaying respiratory signals,the same principles can be applied to display other types ofphysiological signals as well, such as heart rate, blood pressure, bloodoxygen saturation, etc.

FIG. 2 illustrates a visual element 250, in this case a bar graph, whichcan be displayed on a patient monitor to communicate to a user certainaspects of a physiological signal. In some embodiments, the visualelement 250 is a color or monochrome segmented LED, LCD, and/or abit-mapped type display. Other types of displays are also possible andcan be used equally well. The bar graph 250 can include a plurality ofsegments 258, or any other type of sub-division. In certain embodiments,each segment 258 has an inactive state, such as a dark state, and anactive state, such as one or more lit states of varying brightness, orvice versa. In certain embodiments, the lit state includes one or morecolors. The segments 258 can be transitioned between dark and litstates, or between colors, in order to convey information about aphysiological signal to a user.

One or more segments 258 can make up a middle portion 252 of the bargraph 250. Other groupings of segments 258 can make up a first extremityportion 254 (e.g., an upper extremity portion) and a second extremityportion 256 (e.g., a lower extremity portion) of the bar graph 250. Insome embodiments, the upper 254 and lower 256 extremity portions of thebar graph 250 are each indicative of relatively larger magnitudes ofvalues of an acquired physiological signal, or some characteristicderived from the acquired physiological signal, than is the middleportion 252. In other embodiments, however, one of the extremityportions may represent lesser magnitudes than the other, while themiddle portion can represent magnitudes between the greater and lessermagnitudes represented by the extremity portions.

In some embodiments, the bar graph 250 is calibrated. For example, thebar graph 250 can be calibrated in units of energy in a physiologicalsignal or, in the case of respiratory signals, in units of respiratoryvolume. Other calibration units are also possible. In some embodiments,a calibration scale is explicitly indicated on or near the bar graph 250to communicate quantitative information to an observer about thestrength of a physiological signal. In certain embodiments, thecalibration scale of the bar graph 250 is re-configurable, whethermanually or automatically, according to the ranges of values present inthe physiological signal. For example, in the case of a respiratorysignal of a patient with relatively shallow breathing, the dynamic rangeof the calibration scale can be decreased so that the signal extendsover a greater portion of the bar graph 250. In cases where a patient isbreathing very deeply, the dynamic range of the calibration scale can beincreased to avoid clipping of the visual depiction of the respiratorysignal.

The bar graph 260 can also include a value indicator 260 which actuatesin time, e.g. by transitioning bar graph segments 258 between dark andlit states, as the physiological signal changes. In some embodiments,the value indicator 260 is a grouping of one or more segments 258, thenumber of which changes as the value indicator 260 actuates, of thevisual element 250. The value indicator 260 can be indicative of anycharacteristic of an acquired physiological signal and can actuateanywhere along the bar graph 250. For example, the value indicator 260can represent the amplitude of a physiological waveform at a point intime, the amplitude of a selected frequency range of the physiologicalsignal over a specified time period, or the intensity of thephysiological signal at a point in time.

Other characteristics of a physiological signal can also be representedby the value indicator 260. For example, in the case of a respiratorysignal, the value indicator 260 can represent an indication of theacoustic volume of breathing sounds picked up by an acoustic sensor 120.In some embodiments, an indication of the acoustic volume of a patient'srespiratory sounds is related to the amplitude of a relatively lowfrequency envelope of a sound waveform detected by the sensor 120. Thevalue indicator 260 can also represent the respiratory rate of apatient, the depth of breathing, or any other type of informationrelated to a respiratory signal, including a quality of a respiratorysignal (see FIG. 11).

It should be understood that while FIG. 2 illustrates one embodiment ofa value indicator, many different types of value indicators can be usedin various embodiments. The value indicator 260 illustrated in FIG. 2 isone that is well-suited to embodiments where the visual element 150includes a bar graph. However, other types of value indicators may bebetter-suited to other types of visual elements 150. The term “valueindicator,” in addition to having its ordinary meaning, is intended torefer to any type of visual indicator capable of graphicallycommunicating to a user a value associated with a physiological signal,including amplitude, frequency, etc. related to a physiological signal.

In certain embodiments, the value indicator 260 expands in length toindicate increases in the value or magnitude of a selectedcharacteristic of the physiological signal. Conversely, the valueindicator may contract in length to indicate decreases in the value ormagnitude of the signal. While the value indicator 260 is shown in FIG.1 as only extending from the middle portion 252 into the upper extremityportion 254 of the bar graph 250, in other embodiments, it may extendinto both extremity portions 254, 256 simultaneously.

The value indicator 260 can change colors and/or flash as it actuates asan additional method of conveying information to a user. For example,the value indicator 260 could be displayed in red for relatively smallvalues or magnitudes of a respiratory signal, which may correspond toshallow breathing by a patient. In other embodiments, the valueindicator 260 flashes between dark and lit states to indicate shallowbreathing. If the patient's breathing increases to normal levels,however, the value indicator 260 may change to green or cease flashing.Similar methods of changing colors of the value indicator 260 or causingit to flash can be used to indicate other aspects of a respiratorysignal, such as if the patient's respiratory rate drops below apredetermined or user-selected threshold.

In certain embodiments, the middle portion 252 of the bar graphindicates a transition between two or more different physiologicalstates. The states can, for example, be any detectable or distinctphysiological event, phase, or condition. In some, but not all,embodiments, a transition between physiological states represents theoccurrence or presence of a distinct physiological event or condition,rather than simply a greater or lesser degree of a continuingphysiological event or condition. In embodiments where the bar graph 260is used to communicate values of an acquired patient respiratory signal,the middle portion 252 of the bar graph 250 can indicate a transitionbetween inspiration and expiration in the patient's respiratoryactivity, each of which is a distinct phase of respiratory activity. Inother words, when a value in the middle portion 252 of the bar graph ismarked, it is an indication of the patient transitioning betweeninspiration and expiration. In other embodiments, the middle portion 252marks a transition of a physiological signal between normal and abnormalvalues. For example, the middle portion 252 could mark where a patient'sblood oxygen saturation transitions between healthy and dangerouslevels.

In addition to the generally rectangular shaped bar graph shown in FIG.2, other bar graph shapes are also possible. For example, FIG. 3illustrates a diamond-shaped visual element 350. Much like the bar graph250, the diamond-shaped visual element 350, or diamond graph, caninclude a plurality of segments 358, one or more of which can make up amiddle portion 352 as well as upper 354 and lower 356 extremityportions. The diamond graph can also include an actionable valueindicator 360. It should be understood that, while the bar graph 250 andthe diamond graph 360 are each shown as comprising of a number ofdiscrete segments 258, 358, this is not required. Furthermore, those ofskill in the art can recognize a wide variety of variations in shapes,sizes, colors, etc. of the visual elements disclosed in thisspecification which can be used in various embodiments.

While the visual element 150 of FIG. 1 may be a bar graph, as describedherein, many other shapes and embodiments are also possible. Forexample, the visual element 150 can be any graphical shape or symbolwith a reference point about which the graphical shape or symbolextends, expands, or otherwise modulates in at least two directions. Inone embodiment, the visual element 150 is a circle (not shown), thoughother shapes can also be used, whose size increases and decreases inresponse to changes in a physiological signal, such as a respiratorysignal. For example, the circle may have an initial diameter that isindicative of a transition between two or more physiological states. Inone embodiment, the diameter of the circle increases during a firstphysiological state, such as patient inspiration, while the diameterdecreases during a second physiological state, such as patientexpiration. Therefore, when the diameter of the circle is larger thanthe initial diameter, an observer can see that the patient is in a firstphysiological state. When the diameter of the circle is smaller than theinitial diameter, an observer can see that the patient is in a secondphysiological state. Many other types of visual elements 150 are alsopossible.

FIG. 4A is a series of depictions of the visual element of FIG. 2 shownat different times as a physiological signal (e.g., a respiratorysignal) fluctuates. FIG. 4A includes still frames of a bar graph 450 attimes t1, t2, t3, t4, and t5 as the value indicator 460 actuates inresponse to changes in a patient's respiratory signal. In this example,the value indicator 460 represents the acoustic volume of therespiratory sounds picked up by the acoustic sensor 120.

FIG. 4B is a flowchart that further describes the illustrations in FIG.4A. At block 482, a processor (not shown) in a physiological monitoringsystem (e.g., 105) receives physiological information from a patientsensor (e.g., 120). At block 484, the processor determines the value ofthe physiological signal at a selected time. At block 486, the processorcauses the value of the physiological signal at the selected time to bedisplayed on a patient monitor (e.g., 110) by actuating a valueindicator in at least two directions, relative to a reference point,simultaneously. This process can be performed repeatedly for each of aplurality of selected times, as seen in FIG. 4A.

Returning now to FIG. 4A, at time t1, the value indicator 460 shows thatthe acoustic volume of the patient's breathing is relatively small. Thiscan occur in a respiratory signal during an instant between inspirationand expiration (or between expiration and inspiration) by a patientwhere substantially no breathing sound is detected. At time t2, thevalue indicator 460 has expanded to indicate the detection of a greateracoustic volume. In this embodiment, both the upper and lower extremityportions of the bar graph 450 are representative of relatively greatermagnitudes of the acoustic volume of the respiratory signal than is themiddle portion of the bar graph 450. Thus, the value indicator expandsboth in the direction of the upper extremity portion of the bar graph450 as well as the lower extremity portion, in this case, by asubstantially equal amount. At time t3, the value indicator 460 expandseven further in both directions and indicates a relatively loud acousticrespiratory sound. Relatively large acoustic respiratory sounds, such asthis, are typically detected during the middle portion of a patientinspiratory or expiratory phase. At time t4, the value indicator 460 hascontracted somewhat, representing a decrease in the acoustic volume ofthe patient's respiratory signal. Finally, at time t5, the valueindicator 460 contracts to the middle portion of the bar graph 450,indicating that the patient has completed one inspiratory phase and istransitioning to an expiratory phase, or vice versa.

In the embodiment illustrated in FIG. 4A, the middle portion of the bargraph 450 is indicative of a transition between inspiratory andexpiratory phases in the patient's respiratory activity. As the patientinhales, the acoustic volume of the patient's breathing soundsincreases, causing the value indicator to expand in the direction ofboth extremity portions of the bar graph 450 until such time as theacoustic volume reaches its peak and begins to taper off, causing thevalue indicator to contract back toward the middle portion of the bargraph 450. The patient can then begin to exhale, at which point theacoustic volume of the patient's breathing sounds can increase onceagain and the cycle shown in FIG. 4 can generally repeat itself, thoughthe maximum value detected during inspiratory and expiratory phases, aswell as the time to complete each phase, may not be equal. The series ofbar graphs 450 shown in FIG. 4 can, therefore, be representative ofpatient inspiration or expiration. In certain cases it may be desirableto distinguish patient inspiration from expiration. For example, thevalue indicator 460 could be displayed in green during inspiration andin blue during expiration. In other embodiments, the value indicator 460could blink during one respiratory phase while remaining solid duringthe other. Other mechanisms for distinguishing between patientinspiration and expiration in this embodiment are also possible.

A multi-directional visual element such as illustrated and describedwith respect to FIGS. 2-8A provides several clinical advantages incertain embodiments. For example, clinical monitors typically display amultitude of data related to many different physiological parameters ofa patient. Some monitors display several numerical values related to apatient's overall health, such as blood pressure, pulse rate, bloodoxygen concentration or saturation, etc. Monitors also often displayseveral graphical images, or waveforms, as well. Although suchinformation can be clinically useful to a medical provider, in somecases the quantity of information provided on a physiological monitor'sdisplay can cause confusion. For example, a clinician may be overwhelmedwith the quantity of information provided and may not find theparticular information desired when quickly glancing at the monitor'sdisplay. In such cases it is particularly useful to provide certaintypes of physiological information with a unique visual element that canbe quickly discerned by a clinician. By doing so, the medicalpractitioner can become accustomed to visualizing particularphysiological information (e.g., respiratory information) with aparticular visual element (e.g., those described with respect to FIGS.2-8A). This can allow the medical practitioner to quickly find theinformation of interest from an information-rich visual display.

FIG. 5A is another example of a series of depictions of the visualelement of FIG. 2 shown at different times as a physiological signal(e.g., a respiratory signal) fluctuates. The value indicator 560indicates the acoustic volume of the respiratory sounds detected by theacoustic sensor 120. Both extremity portions of the bar graph 550 arerepresentative of relatively larger magnitude values of the acousticvolume of the respiratory signal than is the middle portion of the bargraph. However, the value indicator 560 in this embodiment actuates inthe region of one of the extremity portions of the bar graph 550 at atime. For example, the upper extremity portion of the bar graph 550 cancorrespond to a first phase of a physiological event (e.g., therespiratory signal which correspond to a patient inspiratory phase),while the lower extremity portion of the bar graph can correspond to asecond phase of a physiological event (e.g., an expiratory phase).Therefore, the value indicator 560 represents different physiologicalstates, phases, conditions, activities, etc. along different directions,or in different regions.

FIG. 5B is a flowchart that further describes the illustrations in FIG.5A. At block 582, a processor (not shown) in a physiological monitoringsystem (e.g., physiological monitoring system 105 or any other systemdescribed herein) receives physiological information from a patientsensor (e.g., patient sensor 120 or any other sensor described herein).At block 584, the processor determines the value of the physiologicalsignal at a selected time. At block 586, the processor determines aphysiological state of the patient at the selected time, as representedby the value of the physiological signal at that time. If the patient isin a first physiological state (e.g., inspiration) at decision block588, then the processor causes the value of the physiological signal tobe displayed in a first portion of a visual element. If the patient isin a second physiological state (e.g., expiration) at decision block592, then the processor causes the value of the physiological signal tobe displayed in the second portion of the visual element. If the patientis not in either of the first or second physiological states, then, insome embodiments, it can be assumed that the patient is transitioningbetween the first and second physiological states, and the value of thephysiological signal is displayed accordingly at block 596. This processcan be performed repeatedly for each of a plurality of selected times,as seen in FIG. 5A.

Returning now to FIG. 5A, at time t1, the value indicator 560 shows thata relatively small acoustic volume has been detected. Again, duringnormal respiratory activity this corresponds to a transition betweenpatient inspiration and expiration. At time t2, the value indicator 560expands in the region of the upper extremity portion of the bar graph550 to indicate the detection of relatively loud patient inspirationsounds. At time t3, the value indicator 560 contracts back to the middleportion of the bar graph 550, indicating the end of the inspiratoryphase. The position of the value indicator 560 at time t4 corresponds tothe detection of a moderately loud expiratory signal. Later, at time t5,the acoustic volume of the patient's expiratory action is shown to havedecreased somewhat before it can eventually return back to the middleportion of the bar graph 550, indicating the completion of the patient'sexpiratory phase. As illustrated in FIG. 5A, the acoustic volume of apatient's breathing sounds during inspiratory and expiratory phases doesnot necessarily reach the same maximum value. Nor are the tworespiratory phases necessarily of equal duration.

FIGS. 4A, 4B, 5A, and 5B merely represent two examples of ways in whicha value indicator can actuate in response to changes in a patient'srespiratory, or other physiological, signal according to differentembodiments. In this way, a patient's respiratory activity can be easilymonitored by a caregiver observing the respiratory monitor 110. Asdiscussed previously, a patient's respiratory activity can becontinuously monitored by an acoustic sensor 120 and transmitted to thepatient respiratory monitor 110. The respiratory monitor 110 can includecircuitry to sample the acquired continuous time respiratory signal andconvert it into a digital representation. This operation results in adiscrete series of time samples which approximate the continuous-timerespiratory signal. The respiratory monitor 110 can also include aprocessor to analyze the respiratory signal and to cause a valueindicator to actuate in accordance with changes in the respiratorysignal over time, as illustrated in FIGS. 4A, 4B, 5A, and 5B.

In some embodiments, one respiratory data point is displayed by a visualelement (e.g., visual element 150 or other visual elements describedherein) for every time sample of the continuous-time signal. In otherwords, the value indicator actuation refreshes once for each time sampleof the respiratory signal, e.g., if the continuous-time respiratorysignal is sampled 60 times per second, the value indicator refreshes 60times per second as well. However, the series of respiratory data pointsdisplayed by a visual element can also be different than the number oftime samples that are taken from the continuous-time signal. Forexample, if the continuous-time respiratory signal is sampled 60 timesper second, the value indicator may be configured to only refresh forevery third time sample. In other embodiments, a plurality of timesamples are combined to form a single value in the series of data pointsdisplayed by the visual element. For example, the value indicator can beconfigured to display a series of data points where each data pointrepresents the average (e.g., a moving average) or median of a group oftime samples in order to smooth the actuation of the value indicator. Itis also possible for the value indicator to be configured to actuate ata higher rate than the sampling rate of the continuous-time respiratorysignal by interpolating between time samples.

Some embodiments can be configured to display more than one data point(e.g., a value) at a time. For example, FIG. 6 is a schematicrepresentation of a visual element capable of simultaneously displayinga plurality of values associated with a physiological signal (e.g., arespiratory signal). The visual element 650 includes an array ofsegments 658. The visual element 650 also includes a middle portion 652,as well as upper 654 and lower 656 extremity portions which areindicative of differing values of a respiratory, or other physiological,signal. Each of the five columns of segments represents a separate valuein a series of data points displayed on the visual element 650. Forexample, the first column of segments can represent the value of aphysiological signal at time t1, the second column can represent thevalue at time t2, etc.

In addition, each column of segments 658 includes a value indicator 660,which actuates in response to changes in a physiological signal asdescribed above. The value indicators 660 in FIG. 6 only have their endpoints illuminated, rather than all intervening segments 658 as well. Inother embodiments, end points and intervening segments 658 are bothilluminated. Other types of value indicators are also possible. Eachvalue indicator 660 can be configured to refresh in turn one afteranother until an end column, e.g., the right-most column, in the visualelement 650 has been reached. At this point the pattern may repeat andthe value indicator in the opposite end column, e.g., the left-mostcolumn, can be refreshed. Other patterns for refreshing the valueindicators 660 are also possible. For example, the value indicators 660can be configured to all refresh simultaneously and hold theirrespective values until the next refresh time. Since the value indicator650 shows a plurality of values, it can be configured to show an entireinspiratory or expiratory phase. In other embodiments, the visualelement 650 can be configured to display entire respiratory periods,i.e., one inspiratory phase and one expiratory phase, or even severalrespiratory periods, at once.

In some embodiments, a visual element (e.g., 150) also includes separateindicators to communicate additional information to an observer. Forexample, FIG. 7A is a schematic representation of a visual element,which includes peak indicators, for displaying a physiological signal(e.g., a respiratory signal). The bar graph 750 includes a middleportion 752, an upper extremity portion 754, and a lower extremityportion 756. The bar graph 750 also includes a value indicator 760 whichcan be configured to actuate in response to changes in a detectedrespiratory signal. The bar graph 750 also includes an inspiration peakindicator 770 as well as an expiration peak indicator 772. The peakindicators 770, 772 can be configured to communicate to an observer themaximum magnitude that a patient's respiratory signal has reached duringinspiratory and expiratory phases over a pre-determined time period. Thepeak indicators 770, 772 may be useful to a caregiver as an indicationof the history of the patient's breathing activity and may aid indiagnoses or in decision making related to the patient's care.

In one embodiment, the peak indicators 770, 772 of FIG. 7A are portionsof the bar graph 750 which have been configured to remain activated(e.g., in a lit up state) to show the maximum values or magnitudesattained by the patient's respiratory signal over a period of time. Forexample, the peak indicators 770, 772 remain activated even when thecurrent value shown by the value indicator 760 is other than the peakvalue, or values, represented by the peak indicators 770, 772. Forexample, in FIG. 7A, the value indicator 760 shows a current inspiratorysignal value of a moderate level. The inspiration peak indicator 770,however, shows that the patient's inspiratory signal reached a maximumvalue represented by the upper most segment of the bar graph 750 withinsome pre-determined period of time in its history. Likewise, theexpiration peak indicator 772 shows the maximum value reached by thepatient's expiratory signal over a period of time. In other embodiments,the peak indicator 772 illuminates to a different color than thephysiological signal portion displayed on the bar graph 750.

The peak indicators 770, 772 can be configured to actuate to higherlevels when new peak values in the patient's respiratory signal areattained. Similarly, the peak indicators 770, 772 may actuate to showsmaller values if the patient's breathing activity has trended downwardand previously reached peak values have not been met within the mostrecent pre-determined period of time.

The peak indicators 770, 772 can be configured to show the maximumvalues or magnitudes attained by a patient's respiratory signal over anyperiod of time in the history of the signal. In one embodiment, forexample, the peak indicators 770, 772 show the maximum acoustic volumesreached by a patient's respiratory signal over the course of the pastfive minutes. In some embodiments, the time period is configured to beadjustable by a caregiver.

FIG. 7B is a flowchart that further describes the illustrations in FIG.7A. At block 782, a processor (not shown) in a physiological monitoringsystem (e.g., 105) receives physiological information from a patientsensor (e.g., 120). At block 784, the processor determines the value ofthe physiological signal at a selected time. At block 786, the processorcompares the value of the physiological signal at the selected time toprevious values over a predetermined period of time. If the value of thephysiological signal at the selected time reflects a new peak value,then the processor proceeds from decision block 788 to block 790 whereit actuates a corresponding peak indicator 770, 772 to reflect the newpeak value. Otherwise, at block 792, the processor does not change thepeak indicator 770, 772. This process can be performed over for each newvalue of the physiological signal.

As illustrated in FIG. 7A, the peak indicators 770, 772 may be asegment, or other portion, of the bar graph 750. In these embodiments,the peak indicators 770, 772 can be displayed in different colors fromthe value indicator 760 for clarity in identifying the peak values ormagnitudes. In other embodiments, the peak indicators 770, 772 may beconfigured to blink on and off. In still other embodiments, the peakindicators 770, 772 may be located adjacent the bar graph rather thanbeing a part of the bar graph and may include an icon, arrow, or othergraphical element. Other arrangements are also possible and can berecognized by those of skill in the art.

Some embodiments include additional types of indicators. For example,FIG. 8A is a schematic representation of a visual element, whichincludes goal indicators, for displaying a physiological signal (e.g., arespiratory signal). The bar graph 850 includes goal indicators 874, 876which represent a value of a respiratory, or other physiological, signalfor which a patient is to strive to reach. In the case of respiratorysignals, this type of goal indicator can be beneficial to patients inneed of exercising their lungs while recovering from surgery or astherapy for some other medical condition. Certain embodiments include aninspiratory goal indicator 874 and an expiratory goal indicator 876.Each of these goal indicators 874, 876 is a visual cue that indicates toa patient a target value to try to reach in his or her breathing.

In FIG. 8A, for example, if the value indicator 860 is understood toshow the instant where the patient's inspiratory phase has reached itspeak value or magnitude, which in this case is relatively low, thepatient can see from the bar graph that he or she must breathe moredeeply in order to reach the target value represented by the inspiratorygoal indicator 874. Thus, the goal indicators 874, 876 help a patientstrive to reach a desired level of breathing activity, whether for thepurposes of recovery, testing, or some other reason. In someembodiments, the goal indicators 874, 876 are set and reconfigured by acaregiver, such as a doctor or nurse, or by the patient himself.

The goal indicators 874, 876 can be a segment, or other portion, of thebar graph 850, such as an LED, LCD, and/or an icon, color, sound, orcombination thereof. In such cases it may be desirable to display thegoal indicators in a color other than that used for the value indicator860. In some embodiments, the goal indicators 874, 876 are configured toblink, for example, when the patient achieves the targeted value of thephysiological signal. In still other embodiments, the goal indicators874, 876 are accompanied by an audible indicator which sounds when thepatient reaches the targeted goal. Many other configurations fordisplaying the goal indicators and signaling when the goal has been metare possible as well.

FIG. 8B is a flowchart that further describes the illustrations in FIG.8A. At block 882, a processor (not shown) in a physiological monitoringsystem receives physiological information from a patient sensor. Atblock 884, the processor determines the value of the physiologicalsignal at a selected time. At block 886, the processor compares thevalue of the physiological signal at the selected time to a goal valuethat has been previously inputted by a caregiver or by the patient. Ifthe value of the physiological signal at the selected time meets orexceeds the goal value, then the processor proceeds from decision block888 to block 890 where it causes an acknowledgement that the goal hasbeen reached to be given. This acknowledgement can be, for example, anaudible sound. Otherwise, at block 892, the processor causes no suchacknowledgement to be given. This process can be performed over for eachnew value of the physiological signal.

Some embodiments include more than one type of additional indicatorbeyond a value indicator. This is represented in FIG. 9, which is aschematic representation of a visual element that includes a pluralityof types of indicators for displaying a physiological signal (e.g., arespiratory signal). The bar graph 950 includes peak indicators 970,972, as well as goal indicators 974, 976. The bar graph 950 alsoincludes a middle portion 952, an upper extremity portion 954, a lowerextremity portion 956, and a value indicator 960 which is configured toactuate in response to changes in a detected physiological signal. InFIG. 9, it can be seen that the patient's respiratory signal has reacheda peak value or magnitude marked by the peak indicators 970, 972 thatstill falls short of the patient's targeted goal, as marked by the goalindicators 974, 976. Thus the patient, or a caregiver, can recognizethat the patient should continue to strive to breathe more deeply.

Additional types of indicators can also be included in variousembodiments. As is described herein, these indicators can be configuredas portions of a bar graph, for example. They may also be numbers,letters, or symbols located adjacent a visual element such as a bargraph. In some embodiments, indicators described herein are actionablein response to changes in a physiological signal. For example, inaddition to the peak and goal indicators described above, a bar graph950, or other type of visual element (e.g., visual element 150 or anyother visual element described herein), can include indicators to showaverage values of a patient's respiratory signal during inspiratory orexpiratory phases. The bar graph 950 could also include short-term peakindicators which are configured to represent value or magnitude peaksattained during a relatively short-term history of the patient'srespiratory activity as well as long-term peak indicators which areconfigured to represent value or magnitude peaks attained over thecourse of a longer period of time. It should be apparent to those ofskill in the art that the bar graph 950, or other type of visualelement, can also include many other types of indicators to communicateto an observer any type of information related to a physiologicalsignal.

Some embodiments include visual elements with additional information inthe form of text, numbers, images, icons, or symbols, for example. Inone embodiment, a visual element includes numbers which indicate therespiratory rate (e.g., breaths per minute) and/or respiratory period(e.g., seconds per breath) of a patient. A visual element can alsoinclude a numerical depiction of a value related to a physiologicalsignal or an indication of signal quality (see FIG. 11). Other types ofinformation that would be recognized by those in the skill as having arelationship to a physiological signal or of being of some benefit to acaregiver can also be included with the visual element.

In some embodiments, the patient monitor 110 also includes a speaker orother device capable of producing audible sounds. The patient monitor110 can be configured to output a sound that varies in response tochanges in a physiological signal. For example, the patient monitor 110can output a sound that increases and decreases in volume in response tochanges in a physiological signal. In one embodiment, the soundincreases as the value or magnitude of the signal increases, anddecreases as the value or magnitude of the signal decreases. In someembodiments, the pitch of the sound varies in response to changes in thephysiological signal. For example, the pitch of the sound may increaseas the value or magnitude of the signal increases, and may decrease asthe value or magnitude of the signal decreases. Some embodiments produce“beeps” or other sounds that occur closer together or further apart intime in response to changes in the physiological signal. Someembodiments of the physiological monitor 110 output one sound duringinspiration and a different sound during expiration of a respiratorysignal as a non-visual indication of the different phases of therespiratory signal.

In some embodiments, the speaker is also configured to emit alarms whena patient enters into a dangerous or undesirable condition. For example,if the physiological monitor 110 detects a temporary cessation in thepatient's breathing, such as might occur in a patient with apnea, thespeaker can emit an alarm. The speaker may also be configured to emit analarm if the patient's respiratory rate or depth of respirationdecreases beyond a certain threshold.

FIG. 10 illustrates an embodiment of a sensor system 1000 including asensor assembly 1001 and a monitor cable 1011 suitable for use with anyof the physiological monitors and cables described herein. The sensorassembly 1001 includes a sensor 1015, a cable assembly 1017, and aconnector 1005. The sensor 1015, in one embodiment, includes a sensorsubassembly 1002 and an attachment subassembly 1004. The cable assembly1017 of one embodiment includes a sensor 1007 and a patient anchor 1003.A sensor connector subassembly 1005 is connected to the sensor cable1007.

The sensor connector subassembly 1005 can be removably attached to aninstrument cable 1011 via an instrument cable connector 1009. Theinstrument cable 1011 can be attached to a cable hub 1020, whichincludes a port 1021 for receiving a connector 1012 of the instrumentcable 1011 and a second port 1023 for receiving another cable. The hub1020 is an example of the splitter cable described above, and as such,can include decoupling circuitry. In certain embodiments, the secondport 1023 can receive a cable connected to an optical sensor (e.g., apulse oximetry sensor) or other sensor. In addition, the cable hub 1020could include additional ports in other embodiments for receivingadditional cables. The hub includes a cable 1022 which terminates in aconnector 1024 adapted to connect to a physiological monitor (notshown).

The sensor connector subassembly 1005 and connector 1009 can beconfigured to allow the sensor connector 1005 to be straightforwardlyand efficiently joined with and detached from the connector 1009.Embodiments of connectors having connection mechanisms that can be usedfor the connectors 1005, 1009 are described in U.S. patent applicationSer. No. 12/248,856 (hereinafter referred to as “the '856 application”),filed on Oct. 9, 2008, which is incorporated in its entirety byreference herein. For example, the sensor connector 1005 could include amating feature (not shown) which mates with a corresponding feature (notshown) on the connector 1009. The mating feature can include aprotrusion which engages in a snap fit with a recess on the connector1009. In certain embodiments, the sensor connector 1005 can be detachedvia one hand operation, for example. Examples of connection mechanismscan be found specifically in paragraphs [0042], [0050], [0051],[0061]-[0068] and [0079], and with respect to FIGS. 8A-F, 13A-E, 19A-F,23A-D and 24A-C of the '856 application, for example.

The sensor connector subassembly 1005 and connector 1009 can reduce theamount of unshielded area in and generally provide enhanced shielding ofthe electrical connection between the sensor and monitor in certainembodiments. Examples of such shielding mechanisms are disclosed in the'856 application in paragraphs [0043]-[0053], [0060] and with respect toFIGS. 9A-C, 11A-E, 13A-E, 14A-B, 15A-C, and 16A-E, for example.

In an embodiment, the acoustic sensor assembly 1001 includes a sensingelement, such as, for example, a piezoelectric device or other acousticsensing device. The sensing element can generate a voltage that isresponsive to vibrations generated by the patient, and the sensor caninclude circuitry to transmit the voltage generated by the sensingelement to a processor for processing. In an embodiment, the acousticsensor assembly 1001 includes circuitry for detecting and transmittinginformation related to biological sounds to a physiological monitor.These biological sounds can include heart, breathing, and/or digestivesystem sounds, in addition to many other physiological phenomena. Theacoustic sensor 1015 in certain embodiments is a biological soundsensor, such as the sensors described herein. In some embodiments, thebiological sound sensor is one of the sensors such as those described inthe '883 application. In other embodiments, the acoustic sensor 1015 isa biological sound sensor such as those described in U.S. Pat. No.6,661,161, which is incorporated by reference herein in its entirety.Other embodiments include other suitable acoustic sensors.

The attachment sub-assembly 1004 includes first and second elongateportions 1006, 1008. The first and second elongate portions 1006, 1008can include patient adhesive (e.g., in some embodiments, tape, glue, asuction device, etc.). The adhesive on the elongate portions 1006, 1008can be used to secure the sensor subassembly 1002 to a patient's skin.One or more elongate members 1010 included in the first and/or secondelongate portions 1006, 1008 can beneficially bias the sensorsubassembly 1002 in tension against the patient's skin and reduce stresson the connection between the patient adhesive and the skin. A removablebacking can be provided with the patient adhesive to protect theadhesive surface prior to affixing to a patient's skin.

The sensor cable 1007 can be electrically coupled to the sensorsubassembly 1002 via a printed circuit board (“PCB”) (not shown) in thesensor subassembly 1002. Through this contact, electrical signals arecommunicated from the multi-parameter sensor subassembly to thephysiological monitor through the sensor cable 1007 and the cable 1011.

In various embodiments, not all of the components illustrated in FIG. 10are included in the sensor system 1000. For example, in variousembodiments, one or more of the patient anchor 1003 and the attachmentsubassembly 1004 are not included. In one embodiment, for example, abandage or tape is used instead of the attachment subassembly 1004 toattach the sensor subassembly 1002 to the measurement site. Moreover,such bandages or tapes can be a variety of different shapes includinggenerally elongate, circular and oval, for example. In addition, thecable hub 1020 need not be included in certain embodiments. For example,multiple cables from different sensors could connect to a monitordirectly without using the cable hub 1020.

Additional information relating to acoustic sensors compatible withembodiments described herein, including other embodiments of interfaceswith the physiological monitor, are included in U.S. patent applicationSer. No. 12/044,883, filed Mar. 7, 2008, entitled “Systems and Methodsfor Determining a Physiological Condition Using an Acoustic Monitor,”(hereinafter referred to as “the '883 application”), the disclosure ofwhich is hereby incorporated by reference in its entirety. An example ofan acoustic sensor that can be used with the embodiments describedherein is disclosed in U.S. patent application Ser. No. 12/643,939,incorporated above.

Freshness Indicator

Referring to FIG. 11, a respiratory analysis system 1100 is shown. Therespiratory analysis system 1100 can calculate one or more parametersrelated to an acoustic signal obtained from a patient. The respiratoryanalysis system 1100 can calculate, among other parameters, respiratoryrate (sometimes referred to as RR), respiratory signal quality (RSQ),and freshness of the respiratory rate calculation. Advantageously, incertain embodiments, the respiratory analysis system 1100 can outputdata and/or indicators reflecting one or more of these parameters,thereby assisting clinicians with assessing a health status of apatient.

The respiratory analysis system 1100 includes three example modules inthe depicted embodiment. These modules include a respiratory ratecalculator 1110, an RSQ calculator 1120, and a freshness calculator1130. Each of these modules can include hardware and/or software forperforming certain tasks. An acoustic signal 1102 is received by therespiratory analysis system 1100 and is used by one or more of themodules to perform these tasks. The acoustic signal 1102 can be obtainedfrom an acoustic sensor, such as any of the sensors described above,coupled to a living patient.

The respiratory rate calculator 1100 can analyze the acoustic signal1102 to determine a respiratory rate measurement for the patient. Therespiratory rate measurement can vary with time. The respiratory ratecalculator 1100 can output the respiratory rate measurements 1142 forpresentation to a clinician. For example, the respiratory ratecalculator 1100 can output the respiratory rate measurements 1142 to adisplay or to another clinician device over a network (such as a nurse'sstation computer in a hospital).

The RSQ calculator 1120 can calculate an objective measure of thequality of the acoustic signal 1102. The RSQ calculator 1120 can, forinstance, quantitatively determine how corrupted the acoustic signal1102 is by noise, how similar the acoustic signal 1102 is to knownwaveform characteristics of respiratory signals, and the like. Based atleast in part on this analysis, the RSQ calculator 1120 can output anRSQ indicator 1144 that reflects the calculated quality of the acousticsignal 1102. The RSQ calculator 1120 can output the RSQ indicator 1144to a display or to another clinician device over a network.Advantageously, in certain embodiments, the RSQ indicator 1144 can beimplemented as any of the visual indicators or elements described above.For instance, the RSQ indicator 1144 can be a bidirectional bar graph.As signal quality changes, the bidirectional bar graph could changeaccordingly.

The RSQ indicator 1144 could be a unidirectional bar graph instead of abidirectional bar graph. The RSQ indicator 1144 can also be a binaryindicator, indicating low or high RSQ. The RSQ indicator 1144 could alsobe a numerical value, such as a percentage or the like. In anotherembodiment, the RSQ indicator 1144 can be an occurrence indicator, suchas the occurrence indicator described in U.S. Pat. No. 6,996,427, titled“Pulse Oximetry Data Confidence Indicator,” filed Dec. 18, 2003, thedisclosure of which is hereby incorporated by reference in its entirety.Any combination of the indicators described herein and/or other types ofindicators could be used.

The freshness calculator 1130 calculates a freshness or relevance of therespiratory rate measurement 1142. In some situations, the respiratoryrate calculator 1110 and/or the RSQ calculator 1120 might determine thata calculated respiratory rate measurement 1142 is invalid, of lowquality, or cannot be measured. An invalid respiratory rate measurement1142 can be, for example, a measurement that is not physiologicalpossible (such as a measurement that is too high). An invalidmeasurement can also be a measurement that changes rapidly over a shortperiod of time. One option when invalid or other low qualitymeasurements occur is to discard the invalid or low quality respiratoryrate value and not display a new measurement until a valid or higherquality value is obtained. However, not displaying a respiratory ratevalue (or showing zero) can confuse a clinician if the patient is stillbreathing.

Thus, instead of displaying no (or zero) value in low quality signalconditions, the respiratory rate calculator 1110 can continue to outputthe previous respiratory rate measurement 1142 for a certain amount oftime. This amount of time can be determined by the freshness calculator1130. The freshness calculator 1130 can include a counter, timer, or thelike that increments (or decrements) as soon as a low or invalid signalcondition is detected by the respiratory rate calculator 1110 or the RSQcalculator 1120. When the freshness calculator 1130 determines that acertain amount of time has elapsed, for example, by comparison with apredetermined threshold time value, the freshness calculator 1130 cancause the respiratory rate calculator 1110 to output a zero or norespiratory rate value. Conversely, if while the freshness calculator1130 is incrementing (or decrementing) the counter the respiratory ratecalculator 1110 produces a valid or higher quality respiratory ratemeasurement 1142, the freshness calculator 1130 can reset the counter.

The amount of time elapsed before the freshness calculator 1130 outputsa zero or no respiratory rate value can be user-configurable. Therespiratory analysis system 1100 can, for instance, output a userinterface control on a display of a patient monitor that enables aclinician to adjust the freshness period. This input by a clinician canthen be updated in the freshness calculator 1130. The respiratoryanalysis system 1100 can provide a user interface element on a displayor the like for the clinician to input the freshness timer input 1104.

The freshness calculator 1130 can output a freshness indicator 1146 thatreflects a freshness of the respiratory rate measurement 1142. Thefreshness calculator 1130 can output the freshness indicator 1146 to adisplay or to another clinician device over a network. The freshnessindicator 1146 can be a light, for instance, that turns on when thefreshness calculator 1130 is incrementing (or decrementing) the counter.The light could also change color as the counter is incremented (ordecremented). The freshness indicator 1146 could also be a bar, anumber, or any other visual element. The freshness indicator 1146 couldalso be an audible indicator, such as an audible alarm. The audibleindicator can increase in intensity as the counter is incremented (ordecremented).

In another embodiment, the freshness indicator 1146 can be implementedas a flashing version of a parameter value or other value indicator. Forexample, any numeric value of a parameter can flash to reflect lack of,or a decrease in, freshness. The bidirectional display bar describedabove can also flash to reflect the lack of freshness. The flashing ofthe parameter or other value indicator can increase (or decrease) inrate until a defined time period has expired. After this time period hasexpired, a zero value can be displayed for the parameter. Moreover, whenthe freshness period has expired, an alarm can be triggered.

In yet another embodiment, the freshness indicator 1146 and the RSQindicator 1144 are implemented together, for example, as follows. TheRSQ indicator 1144 can generally indicate changes in signal quality of arespiration or acoustic signal. The freshness of a respiratory ratemeasurement 1142 can be calculated as described above. Instead ofoutputting a separate indicator, the calculated freshness can be used toadjust the output of the RSQ indicator 1144. If a respiratory ratemeasurement 1142 is less fresh, for instance, the RSQ indicator 1144 canreflect this as a lower value, a lower bar (or bars), or the like. Inone embodiment, the RSQ indicator 1144 is lowered by some percentage,such as 5%, 10%, 20%, or some other percentage. In other embodiments,the RSQ indicator 1144 gradually drops toward some minimum value (suchas zero) as the freshness decreases.

Any combination of these features can be used for the freshnessindicator 1146, as well as others.

FIG. 12 illustrates an embodiment of a patient monitor 1200 having arespiration display. The patient monitor 1200 can include any of thefeatures described above. Further, the patient monitor 1200 canimplement any of the displays or other features described above. In thedepicted embodiment, the patient monitor 1200 displays an examplerespiration waveform.

The patient monitor 1200 displays parameter indicators for severalphysiological parameters in the depicted embodiment. Some of theseparameter indicators include an oxygen saturation indicator 1210,hemoglobin, perfusion index, plethysmograph variability index, and otherindicators 1220, and an occurrence graph 1225 reflecting signal qualityfor an optical signal.

Further, the patient monitor 1200 displays an example respiratory rateindicator 1230 that reflects values of a patient's respiratory rate.This value can be obtained using any of the respiratory rate measurementmethods described above. Advantageously, in the depicted embodiment, thepatient monitor 1200 also includes a respiration waveform 1240. Thisrespiration waveform 1240 can represent a patient's time-domainrespiration signal or an envelope of the respiration signal over aperiod of time. The respiration waveform 1240 can be bidirectional orunidirectional in some embodiments. The depicted patient monitor 1200illustrates a bidirectional respiration waveform 1240. A unidirectionalrespiration waveform 1240 might include excursions in a single direction(e.g., positive or negative) from an axis.

The respiration waveform 1240 can reflect an actual respiration signal,providing a clinician with more information about a patient's breathingpattern than just the respiratory rate indicator 1230 alone. Therespiration waveform 1240 can enable a clinician to diagnose patientproblems by observing, for instance, heights and widths of peaks in therespiratory waveform 1240, irregularities in the respiratory waveform1240, spikes of activity in the respiratory waveform 1240, general lowactivity in the respiratory waveform 1240, some combination of the same,or the like.

It should be noted that although several embodiments herein havedescribed a bidirectional display, a unidirectional display can be usedinstead to represent respiratory parameters.

Conditional language used herein, such as, among others, “can,” “could,”“might,” “may,” “e.g.,” and the like, unless specifically statedotherwise, or otherwise understood within the context as used, isgenerally intended to convey that certain embodiments include, whileother embodiments do not include, certain features, elements and/orstates. Thus, such conditional language is not generally intended toimply that features, elements and/or states are in any way required forone or more embodiments or that one or more embodiments necessarilyinclude logic for deciding, with or without author input or prompting,whether these features, elements and/or states are included or are to beperformed in any particular embodiment.

Depending on the embodiment, certain acts, events, or functions of anyof the methods described herein can be performed in a differentsequence, can be added, merged, or left out all together (e.g., not alldescribed acts or events are necessary for the practice of the method).Moreover, in certain embodiments, acts or events can be performedconcurrently, e.g., through multi-threaded processing, interruptprocessing, or multiple processors or processor cores, rather thansequentially.

The various illustrative logical blocks, modules, circuits, andalgorithm steps described in connection with the embodiments disclosedherein can be implemented as electronic hardware, computer software, orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. The described functionalitycan be implemented in varying ways for each particular application, butsuch implementation decisions should not be interpreted as causing adeparture from the scope of the disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the embodiments disclosed herein can be implementedor performed with a general purpose processor, a digital signalprocessor (DSP), an application specific integrated circuit (ASIC), afield programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general purpose processor can be a microprocessor, but in thealternative, the processor can be any conventional processor,controller, microcontroller, or state machine. A processor can also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The blocks of the methods and algorithms described in connection withthe embodiments disclosed herein can be embodied directly in hardware,in a software module executed by a processor, or in a combination of thetwo. A software module can reside in RAM memory, flash memory, ROMmemory, EPROM memory, EEPROM memory, registers, a hard disk, a removabledisk, a CD-ROM, or any other form of computer-readable storage mediumknown in the art. An exemplary storage medium is coupled to a processorsuch that the processor can read information from, and write informationto, the storage medium. In the alternative, the storage medium can beintegral to the processor. The processor and the storage medium canreside in an ASIC. The ASIC can reside in a user terminal. In thealternative, the processor and the storage medium can reside as discretecomponents in a user terminal.

While the above detailed description has shown, described, and pointedout novel features as applied to various embodiments, it can beunderstood that various omissions, substitutions, and changes in theform and details of the devices or algorithms illustrated can be madewithout departing from the spirit of the disclosure. As can berecognized, certain embodiments of the inventions described herein canbe embodied within a form that does not provide all of the features andbenefits set forth herein, as some features can be used or practicedseparately from others. The scope of certain inventions disclosed hereinis indicated by the appended claims rather than by the foregoingdescription. All changes which come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

What is claimed is:
 1. A method of displaying physiological informationon a physiological monitor configured to be coupled to a patient sensoroperative to detect a physiological signal, the method comprising: by aprocessor: receiving a respiration signal from an acoustic respiratorysensor coupled with a patient; outputting a value indicator to a displayof the physiological monitor, the value indicator configured torepresent an envelope amplitude of the respiration signal; expanding thevalue indicator in two directions simultaneously in response toincreasing values of the envelope amplitude of the respiration signalwherein the value indicator is configured to expand from a referenceposition representative of a transition between inspiration andexpiration in the respiration signal; contracting the value indicatoropposite the two directions simultaneously in response to falling valuesof the envelope amplitude of the respiration signal; and changing acharacteristic of the value indicator to visually distinguish betweeninspiration and respiration.
 2. The method of claim 1, wherein saidexpanding and contracting are performed during an expiration cycle. 3.The method of claim 2, wherein said expanding and contracting arefurther repeated during an inspiration cycle.
 4. The method of claim 1,wherein said expanding the value indicator comprises expanding the valueindicator in first and second directions that are substantially oppositeone another.
 5. The method of claim 1, wherein the value indicatorcomprises a bidirectional bar graph.
 6. The method of claim 1, furthercomprising displaying a peak indicator of a maximum value attained bythe envelope amplitude of the respiration signal over a defined periodof time, wherein the peak indicator is configured to remain activatedeven when a current value shown by the value indicator is other than themaximum value.
 7. The method of claim 1, further comprising calculatingrespiratory rate from the respiration signal, calculating a freshness ofthe respiratory rate, and adjusting an output associated with therespiratory rate based at least in part on the calculated freshness. 8.A method of displaying physiological information on a physiologicalmonitor, the method comprising: by a processor: receiving a respirationsignal from a sensor coupled to a patient; activating a visual indicatorof a visual element, the visual indicator configured to represent anamplitude of the respiration signal; and illuminating the visualindicator outwards from a reference position toward both a first endregion and a second end region of the visual element and then inwardsfrom the first and second end regions toward the reference position,responsive to changes in the amplitude of the respiration signal,wherein the reference position is representative of a transition betweeninspiration and expiration, and wherein the visual indicator isconfigured to have a first visual appearance corresponding toinspiration and a second visual appearance corresponding to expiration.9. The method of claim 8, wherein the first and second end regionscomprise opposite ends of the visual element, and wherein the referenceposition is located between said first and second end regions.
 10. Themethod of claim 8, wherein the visual indicator comprises an LED. 11.The method of claim 8, wherein the visual element comprises a bar graph.12. A physiological monitor comprising: a processor configured toreceive physiological information comprising a respiration waveform fromone or more sensors coupled with a patient; and a display comprising avisual element for representing values of an amplitude of therespiration waveform, the visual element comprising: a middle portionrepresenting an reference position, wherein the reference position isrepresentative of a transition between inspiration and expiration, firstand second extremity portions, the first extremity portion extendingfrom the middle portion in a first direction, and the second extremityportion extending from the middle portion in a second direction, and avalue indicator, wherein the processor is configured to illuminate thevalue indicator starting from the reference position and expanding bothto the first and second extremity portions, followed by contracting thevalue indicator at least partway toward the reference position,responsive to changes in the amplitude of the respiration waveform, andwherein the value indicator is configured to have a first visualappearance corresponding to inspiration and a second visual appearancecorresponding to expiration.
 13. The physiological monitor of claim 12,wherein the first and second directions comprise substantially oppositedirections.
 14. The physiological monitor of claim 12, wherein theprocessor is further configured to actuate the value indicator in boththe first and second directions simultaneously.
 15. The physiologicalmonitor of claim 12, wherein the processor is further configured toactuate the value indicator in both the first and second directions bysubstantially equal amounts.
 16. The physiological monitor of claim 12,wherein the visual element comprises a bar graph.
 17. The physiologicalmonitor of claim 12, wherein the visual element comprises a segmenteddisplay.
 18. The physiological monitor of claim 12, further comprising asound-producing device to output a sound that changes in response tochanges in the amplitude of the respiration waveform.
 19. Thephysiological monitor of claim 12, wherein the first visual appearanceis a different color than the second visual appearance.
 20. Thephysiological monitor of claim 12, wherein one of the first visualappearance and the second visual appearance comprises blinking at leasta portion of the value indicator.